Blunted endogenous opioid release following an oral dexamphetamine challenge in abstinent alcohol-dependent individuals.

Addiction has been proposed as a 'reward deficient' state, which is compensated for with substance use. There is growing evidence of dysregulation in the opioid system, which plays a key role in reward, underpinning addiction. Low levels of endogenous opioids are implicated in vulnerability for developing alcohol dependence (AD) and high mu-opioid receptor (MOR) availability in early abstinence is associated with greater craving. This high MOR availability is proposed to be the target of opioid antagonist medication to prevent relapse. However, changes in endogenous opioid tone in AD are poorly characterised and are important to understand as opioid antagonists do not help everyone with AD. We used [11C]carfentanil, a selective MOR agonist positron emission tomography (PET) radioligand, to investigate endogenous opioid tone in AD for the first time. We recruited 13 abstinent male AD and 15 control participants who underwent two [11C]carfentanil PET scans, one before and one 3 h following a 0.5 mg/kg oral dose of dexamphetamine to measure baseline MOR availability and endogenous opioid release. We found significantly blunted dexamphetamine-induced opioid release in 5 out of 10 regions-of-interest including insula, frontal lobe and putamen in AD compared with controls, but no significantly higher MOR availability AD participants compared with HC in any region. This study is comparable to our previous results of blunted dexamphetamine-induced opioid release in gambling disorder, suggesting that this dysregulation in opioid tone is common to both behavioural and substance addictions.

Clinical utility of amyloid PET imaging with (18)F-florbetapir: a retrospective study of 100 patients.

BACKGROUND AND OBJECTIVE: Amyloid-positron emission tomography (PET) imaging (API) detects amyloid-beta pathology early in the course of Alzheimer's disease (AD) with high sensitivity and specificity. (18)F-florbetapir (Amyvid) is an amyloid-binding PET ligand with a half-life suitable for clinical use outside of the research setting. How API affects patient investigation and management in the 'real-world' arena is unknown. To address this, we retrospectively documented the effect of API in patients in the memory clinic. METHODS: We reviewed the presenting clinical features, the pre-API and post-API investigations, diagnosis and outcomes for the first 100 patients who had API as part of their routine work-up at the Imperial Memory Centre, a tertiary referral clinic in the UK National Health Service. RESULTS: API was primarily used to investigate patients with atypical clinical features (56 cases) or those that were young at onset (42 cases). MRI features of AD did not always predict positive API (67%), and 6 of 23 patients with MRIs reported as normal were amyloid-PET positive. There were significantly more cases categorised as non-AD dementia post-API (from 11 to 23). Patients investigated when API was initially available had fewer overall investigations and all patients had significantly fewer investigations in total post-API. CONCLUSIONS: API has a clear impact on the investigation of young-onset or complex dementia while reducing the overall burden of investigations. It was most useful in younger patients, atypical presentations or individuals with multiple possible causes of cognitive impairment.

Pearls & Oy-sters: What Came First, the Bleed or the Fall?: An Aneurysmal Subdural Hemorrhage.

Acute subdural hemorrhages are a common emergency presentation often associated with trauma. However, in the absence of significant trauma, it is important to consider alternative causes. In this case, a 58-year-old woman with trivial trauma after a sudden collapse had bilateral subdural hemorrhages on CT. CT-angiogram revealed anterior communicating artery aneurysm, which had ruptured. This case explores intracerebral aneurysms as a rare cause of subdural hemorrhage that is important to consider in the absence of significant trauma.

Beyond the brain: Extra-axial pathology on diffusion weighted imaging in neuroimaging.

Diffusion-weighted imaging (DWI) has a central role in the assessment of the brain parenchyma, particularly in the context of acute stroke. However, the applications of DWI extend far beyond the brain parenchyma and include the assessment of the extra-axial structures of the head and neck that are included in routine brain imaging. In this pictorial review, the added-value of DWI over other conventional sequences is illustrated through discussion of a broad range of disorders affecting the vasculature, skull, orbits, nasal cavity and salivary glands. This article highlights the requirement for all structures, both intra- and extra-axial, to be carefully reviewed on DWI.

Ultrasound-guided percutaneous splenic biopsy using an 18-G core biopsy needle: our experience with 52 cases.

OBJECTIVE: The spleen is more commonly affected in multiorgan disease, but alternative sites are selected for biopsy owing to perceived haemorrhage risk. If these sites are inaccessible or, less commonly, the spleen is the only disease site, then splenic biopsy is considered, with most studies using a 20- to 22-G needle. The primary aim of biopsy is to exclude underlying malignancy or to obtain histological analysis in known malignancy, usually lymphoma, when reclassification is required for therapy. We present, to our knowledge, the largest series of 18-G ultrasound-guided splenic core needle biopsy assessing diagnostic and complication rates. METHODS: All ultrasound-guided splenic biopsy cases from May 1990 to May 2015 were identified on the radiology information system. Histological diagnosis and complications were identified from laboratory reports, case notes and discharge summaries to assess diagnostic positive and complication rates. Haemorrhages requiring transfusion, embolization or splenectomy, pneumothorax, other significant intra-abdominal injury or death are classified as major complications, whilst conservative haemorrhage management is considered a minor complication. RESULTS: A total of 52 splenic biopsies were performed in 47 patients. A positive diagnostic yield for all biopsies was 90.4%. The major and minor complication rates were 0% and 1.9% (1/52), respectively. CONCLUSION: Ultrasound-guided 18-G splenic biopsy is a safe and accurate procedure with no added risk of complications when compared with smaller needles or biopsy of other abdominal organs. ADVANCES IN KNOWLEDGE: This is the largest case series of ultrasound-guided splenic biopsy with an 18-G needle, and our experience confirms a high diagnostic yield and a complication rate which compares favourably with the biopsy of other abdominal organs.